A study in Britain has revealed that stress during pregnancy could have its affect on the unborn child's health in years to come and researchers suggest that expecting women should be supported during tension-filled times.

The study of English mothers-to-be revealed how going through a major upheaval -- a bereavement or separation -- dramatically raised the odds of their baby suffering ill health by the age of four, Daily Mail reported.

According to the researchers, from the Institute of Psychiatry at King's College London, it is crucial that pregnant women are supported through stressful events.

It was found that the link with chronic conditions was particularly strong, with two bouts of severe stress in pregnancy raising the odds five-fold.

In the study, over 150 mothers-to-be were asked early in their pregnancy and again, just a few weeks before giving birth, about any stressful events affecting them, such as a family bereavement, separation, sudden unemployment and a difficult pregnancy.

Four years later, the same women were interviewed about their children's health, including any illnesses that had led to them visiting their doctor or being hospitalised.

It revealed a clear link with stress in pregnancy and ill health, with trauma early in pregnancy particularly likely to be linked to asthma or infections such as tummy bugs, the British Association for Psychopharmacology's annual conference heard recently.